FlightRecord

Seattle (SEA) to Milwaukee (MKE): On-Time Performance

Data through May 2026

When you fly SEA to MKE matters as much as anything else about the booking: the route swung from 100% on-time in March 2025 to just 70% in August 2024. Across the full period the route averages 84% on-time against a national 78%. Morning departures also hold up better than evening ones (90% vs 70%), which matters most in the rough months.

On-time
84%
arrived <15 min late
Avg delay
8 min
completed flights
Cancelled
0.2%
Flights/day
1.4
last 12 months
Duration
3h 51m
scheduled
Distance
1,694 mi

Monthly on-time trend

Monthly on-time percentage for SEA to MKE flights50%75%100%June 2024: 87% on-time (60 flights)87Jun 2024July 2024: 73% on-time (62 flights)73August 2024: 70% on-time (56 flights)70September 2024: 81% on-time (48 flights)81Sep 2024October 2024: 90% on-time (31 flights)90November 2024: 93% on-time (30 flights)93December 2024: 93% on-time (28 flights)93Dec 2024January 2025: 85% on-time (20 flights)85February 2025: 88% on-time (18 flights)88March 2025: 100% on-time (25 flights)100Mar 2025April 2025: 90% on-time (30 flights)90May 2025: 82% on-time (49 flights)82June 2025: 83% on-time (60 flights)83Jun 2025July 2025: 79% on-time (61 flights)79August 2025: 81% on-time (62 flights)81September 2025: 80% on-time (60 flights)80Sep 2025October 2025: 97% on-time (33 flights)97November 2025: 79% on-time (33 flights)79December 2025: 79% on-time (42 flights)79Dec 2025January 2026: 79% on-time (24 flights)79February 2026: 89% on-time (18 flights)89March 2026: 92% on-time (26 flights)92Mar 2026April 2026: 97% on-time (36 flights)97May 2026: 86% on-time (55 flights)86

Best time to fly from SEA to MKE

Aim for departures around 8 a.m. (92% on-time); avoid 6 p.m. departures (70%).

On-time percentage by scheduled departure hour, SEA to MKE7 a.m.: 91% on-time (342 flights)78 a.m.: 92% on-time (224 flights)89 a.m.: 83% on-time (105 flights)96 p.m.: 70% on-time (291 flights)18scheduled departure hour

By day of week

DayOn-timeAvg delay
Monday81%8 min
Tuesday84%7 min
Wednesday83%7 min
Thursdaybest89%6 min
Friday87%6 min
Saturday82%10 min
Sunday80%10 min

What causes delays on this route

Share of total delay minutes by cause, as reported by carriers to the US DOT.

  • Late-arriving aircraft30%
  • Airline operations41%
  • National airspace system28%
  • Weather1%

Frequently asked questions

How often are flights from SEA to MKE delayed?
16% of SEA–MKE flights arrived 15 or more minutes late (the US DOT definition of a delay) between 2024-06 and 2026-05. The average arrival delay across completed flights was 8 minutes.
What is the best time of day to fly from SEA to MKE?
Departures around 8 a.m. have the best record (92% on-time), while departures around 6 p.m. have the worst (70%). As on most US routes, delays accumulate through the day, so earlier flights are generally safer.
How long is the flight from SEA to MKE?
The scheduled SEA–MKE flight time averages 3h 51m over 1,694 miles. Actual arrival times vary — flights on this route land 15+ minutes late 16% of the time.
How often are SEA to MKE flights cancelled?
0.2% of scheduled flights on this route were cancelled between 2024-06 and 2026-05, at or below the national rate of 1.6%.
What is the worst month to fly from SEA to MKE?
August 2024 was the roughest month in this dataset, with only 70% of arrivals on time. The best was March 2025 at 100%. If your dates are flexible, that 30-point gap is worth planning around.

Based on 967 flights, 2024-062026-05. Source: US DOT Bureau of Transportation Statistics. Updated 2026-07-01.